Interesting... If nitrous oxide has any real potential you should be able to use it by itself I would think. My friend just blew through 10 cartridges in a short space of time using the above method. The first 8 were uneventful, until he realized that relaxation probably has a lot to do with success, and did the last two while laying on the floor. He experienced the desired effects again and remembers coming down more than up. Coming up involved some meaningless train of though, then it's as if there was a flash where he entered this 'blacked out' outside-of-time state before realizing that the balloon deflated because he forgot it was there. There was something going on in the 'flash', but he can't remember what. It may have been colourful or interesting.
The upside so far is the unique nature of the experience. It's not 'psychedelic' in an obviously introspective or visual way, but if you get it right, it's like you cease to exist in physical reality for an immeasurable second. What he can learn from this is not yet clear.
The downside is that this stuff seems to have some SERIOUS addictive potential. He can see why people would go through hundred of cartridges a day. The first thought after if wears off is 'I want some more'. That's generally not a good sign, but it probably has something to do with the experience seeming totally non-threatening and strongly 'disassociative' at the same time. For a brief moment, a large aspect of YOU can cease to exist.

Combined with Cannabis, the N2O experience can be quiet a ride, especially when facilitated with music and a good visualization plugin like milkdrop in Winamp.

I like a little downtempo trip-hop, like Mistake Theory. The software provides the visual games, the music becomes other-worldly, and the N2O proceeds to fracture the ego. It's like a puzzle, however, that you reassemble as you come down. It always goes back together the same way, which is disappointing in a sense, but also reassuring.

Came to the same conclusion years ago... 2 full hits then black out
There is something going on in that dreamlike state but there is nothing to remember.
I had a headache and felt tired when i woke up. Felt like i had been out for hours, but it was only few minutes.
Also i remember to be very happy before, but mildly depressed afterwards..

It is fun to do in company. Everyone fill an balloon and inhale at the same time.
Good for laughs sure, but no more than that.

Maybe i will try it when im tripping someday
could be fun

Your dentist will give you about 50% oxygen and 50% nitrous. Though lately they have been less likely to use nitrous, since there are substitutes. This may lead to visions, but you are not likely to remember them. Like a dream you can't remember. It's too much of a dissociative to be visionary. I take one breath of nitrous hold it till I can't any longer, and then exhale it back into the bag. I take 2-3 breathes of fresh air and then hit the nitrous again. I find one can reuse a lungful of nitrous at least once. Nitrous isn't metabolized by the body, it passes through unchanged. And, you aren't likely to inhale all of it with just one inhale. I find double-vision common with a prolonged nitrous experience using 5 or more carts, but nothing else really visual. And, this might be an effect of oxygen deprivation.

I would love to have a tank of oxygen. Oxygen deprivation takes away from the experience and leaves me with a headache. Remember fresh air isn't nearly 50% oxygen, more like 20%. That means that you really should take a couple breathes of air between hits of nitrous. Also, daily use has shown to actually affect the way you metabolize or absorb vitamin b12.

Getting high, or even influencing an experience through oxygen deprivation isn't very safe or fun. It is kinda like putting a plastic bag over your head. You don't have to go 5 or 6 minutes without oxygen to suffer from oxygen deprivation.